This invention relates to a device for heating and/or air conditioning a vehicle interior. The device is provided with a heater located in an air guide channel and a housing in the shape of a frame aligned transversely to the air flow, and has control flaps to regulate the air volume flowing through.
Devices of this kind are known from DE 41 19 474 A1. In the devices described by that document, an evaporator is located in a housing of an air conditioner and a heater is located behind the evaporator in a bent air guide channel. The heater is aligned in a frame-like housing transversely to an air flow guided through the air guide channel. The air guide channel for the heater, in this case, is provided behind the heater with pivotable control flaps to open or close the air guide channel, which then terminates in a mixing chamber in which an air stream from the evaporator can also enter when corresponding control flaps for this air guide branch are open. Heating or air conditioning devices of this kind are relatively cumbersome because of the need to install control flaps behind the heater and behind the evaporator. In addition, the possibility cannot always be ruled out that when only cooling is required and the heater must therefore be shut off, a certain amount of air will still be heated by the heater, which initially is still warm, and mixed with the cooling air. As a result, immediately desired cooling cannot always be achieved.
In known heating and air conditioning devices of the type mentioned at the outset, the sealing of the heater in its housing is also relatively cumbersome and, as a rule, is achieved by manually applied adhesive seals in order to compensate for manufacturing tolerances.
It is intended to provide, by the present invention, a design for a heating and air conditioning device of the type mentioned above so that manufacture and assembly are simplified and so that undesired residual heating following the shutoff of the heater is prevented as completely as possible.
To achieve this goal, in a device such as that mentioned at the outset, it is proposed to make the housing in two parts and have it consist of a plug-in part for the heater and a housing part mounted on the plug-in side, and to provide the plug-in part and the housing part with elements for opening and closing at least a portion of the free through flow cross section.
As a result of this design, the heater can be inserted in a relatively simple fashion from one side into the plug-in part of the housing and then secured by mounting the second housing part. Since the throughput cross section can now be open or closed on both the air inlet side and the air outlet side of the heater, it becomes relatively simple to prevent the air delivered to the vehicle interior from being subjected to residual heating in the vicinity of the heater, since the heater can be closed off on both sides.
Although it is known from Japanese disclosure document 61-1527 A to provide a box-like housing for a heater with air control flaps on its inlet and outlet sides, that document discloses the heater as aligned with both its inlet and outlet surfaces parallel to the walls of an air guide channel and hence parallel to the airflow. Therefore, the pivotable flaps serve to deflect the flowing air into the inlet cross section of the heater. They are, therefore, made with different widths. Only one deflecting flap is provided on the outlet side. This deflecting flap is in an operating connection with the flaps located on the inlet side and likewise serves to deflect the escaping air.
According to one feature of the invention, the mounted housing part can be a frame that can be snapped elastically onto the plug-in part, and controllable shutter arrangements, controllable at least on the plug-in part, can be provided as opening and closing elements. The shutter arrangements make it possible to close either the entire cross section or only a part thereof. This design also makes it possible to meter precisely the volume of air guided through the heating body, and hence made available, without providing additional air flaps.
According to another feature of the invention, a check valve arrangement can be provided as opening and closing elements on the mounted frame, with the check valves being mounted movably, in an especially simple fashion, in front of the output slots and with the frame of the outlet slots having a supporting surface for the check valves that is aligned diagonally to the horizontal. When the shutter arrangement on the inlet side of the heater in the housing is closed and through flow is prevented, the check valves can pivot downward onto the associated supporting surfaces under their own weight and, in this way, close off the heater on the outlet side, so that residual heating is prevented. No expense is required for controlling such a check valve arrangement.
In order to facilitate insertion of the heater into a housing, or in other words into its plug-in part, the plug-in part can be provided with a circumferential seal against the heater. This seal consists of at least two opposite sides of a sealing strip made of a relatively hard material, especially plastic material, that can be pressed elastically against the heater. This design makes it possible, because of the low frictional forces, simply to push the heater into the plug-in part by applying it against its sealing strips and thus to produce a seal. According to a further feature of the invention, the sealing strip can be supported by a plurality of ribs on the plug-in part, with the ribs consisting of plastic material and being aligned parallel to one another in the flow direction. A design of this kind permits a close fit between the sealing strip and the heater without any problems during installation.
According to yet another feature of the invention, in the area located laterally with respect to the two sealing strips, a seal can be provided on the plug-in part which abuts the heater when the heater is in the installed position. Of course, it is also possible to locate the plug-in housing itself on a mount in the air guide channel and to provide a seal between the mount and the plug-in part so that there is no way for the flowing air to enter the area behind the heater other than through the heater itself in the desired quantity.